Let's throw around some rough numbers:
Based on the drawings, there appear to be positions for the following roles:
2x Information
2x Check-in (I assume also handling boarding)
3x Security
2x Passport / Immigration Checks
Turnaround will probably require 3 ground handling personnel too. So that's a total of 12 employees at any one time. Assuming 2 shifts of 7 hours, that's 24 employees working each day.
Assuming all can be persuaded to work minimum wage, that's a cost of £1260 per day.
A lot of the other costs can be written off - it's already an active airfield, so write off ATC, fire and airport ops expenses. The terminal is also part of an existing building, so write off heating, cleaning etc.
So, expected revenue?
Let's assume it is a 48 seat ATR, operating 2x SEN, 2x DUB and 1x BFS for a total of 5 movements per day.
Based on the quoted costs for Leeds Bradford as reference (1), you can expect the following:
Landing Fees (£15 per tonne - 19 tonnes) - £285 (£1425 for 5 arrivals)
Passenger Fees - Per departing flight:
Passenger Charge: £13.20 per pax
Security Charge: £3.79 per pax
Baggage Screening: £1.09 per pax (regardless of whether they have bags or not)
Total Per Pax: £18.08
Assuming every flight is 50%: £2169.60
Assuming every flight is full: £4339.20
Therefore, the profit per day can be expected to be £2334 - £4504 based on those rough estimates.
Obviously there's a lot of assumptions here. Depending on what the real impact on other costs will be, it may certainly be possible for Carlisle Airport to make a profit from passenger flights. However, it all depends on whether Stobart Air can make a profit off the flights. They will be the more cost sensitive part of the operation - if they can't make a profit, then no-one will.
(1)
https://www.leedsbradfordairport.co....es-and-charges